package opentracing_test
import (
"context"
"testing"
"github.com/opentracing/opentracing-go"
"github.com/opentracing/opentracing-go/mocktracer"
"google.golang.org/grpc/metadata"
kitot "github.com/go-kit/kit/tracing/opentracing"
"github.com/go-kit/log"
)
func TestTraceGRPCRequestRoundtrip(t *testing.T) {
logger := log.NewNopLogger()
tracer := mocktracer.New()
// Initialize the ctx with a Span to inject.
beforeSpan := tracer.StartSpan("to_inject").(*mocktracer.MockSpan)
defer beforeSpan.Finish()
beforeSpan.SetBaggageItem("baggage", "check")
beforeCtx := opentracing.ContextWithSpan(context.Background(), beforeSpan)
toGRPCFunc := kitot.ContextToGRPC(tracer, logger)
md := metadata.Pairs()
// Call the RequestFunc.
afterCtx := toGRPCFunc(beforeCtx, &md)
// The Span should not have changed.
afterSpan := opentracing.SpanFromContext(afterCtx)
if beforeSpan != afterSpan {
t.Error("Should not swap in a new span")
}
// No spans should have finished yet.
finishedSpans := tracer.FinishedSpans()
if want, have := 0, len(finishedSpans); want != have {
t.Errorf("Want %v span(s), found %v", want, have)
}
// Use GRPCToContext to verify that we can join with the trace given MD.
fromGRPCFunc := kitot.GRPCToContext(tracer, "joined", logger)
joinCtx := fromGRPCFunc(afterCtx, md)
joinedSpan := opentracing.SpanFromContext(joinCtx).(*mocktracer.MockSpan)
joinedContext := joinedSpan.Context().(mocktracer.MockSpanContext)
beforeContext := beforeSpan.Context().(mocktracer.MockSpanContext)
if joinedContext.SpanID == beforeContext.SpanID {
t.Error("SpanID should have changed", joinedContext.SpanID, beforeContext.SpanID)
}
// Check that the parent/child relationship is as expected for the joined span.
if want, have := beforeContext.SpanID, joinedSpan.ParentID; want != have {
t.Errorf("Want ParentID %q, have %q", want, have)
}
if want, have := "joined", joinedSpan.OperationName; want != have {
t.Errorf("Want %q, have %q", want, have)
}
if want, have := "check", joinedSpan.BaggageItem("baggage"); want != have {
t.Errorf("Want %q, have %q", want, have)
}
}